DOP-Mii originally known as DOP-IOS MOD, is in short; A homebrew Wii system tool that can do almsot anything to your Wii. Check out the features below.
Features
Works completely online or offline (supports many offline formats such as WAD for offline installation)
Works with a plethora of different controllers
A pretty sexy GUI
Output a detailed report of your Wii's internals to the SD Card
Install an IOS that accepts fakesigning on Wii's that don't have one
Install any IOS to any slot with or without patches applied to the IOS
Upgrade/Downgrade any IOS
Detect and delete stubbed IOSs
Upgrade/Downgrade and install a wide range of channels
Upgrade/Downgrade the System Menu
Upgrade/Downgrade MIOS
Upgrade/Downgrade BC
Upgrade boot2